Heretofore, there has been known a rear vehicle body structure where a rear wheel arch (rear wheel house) has a closed sectional shape defined in its portion from a floor located therebelow to a rear pillar located thereabove (see, for example, patent literature 1 identified below).
More specifically, in the known rear vehicle body structure, a first closed sectional shape is defined with a channel-shaped gusset attached to the outer surface of the rear wheel arch, and a second closed sectional shape is defined with a channel-shaped damper stiffener attached to the upper surface of the rear wheel arch in such a manner to extend from the upper surface of the rear wheel arch to the rear pillar continuously with the first closed sectional shape. Thus, it is possible to increase the mechanical strength of a rear vehicle body section without decreasing the interior space of a vehicle compartment.
If, in the rear vehicle body structure disclosed in patent literature 1, the mechanical strength of the rear vehicle body section is to be even further increased, it is conceivable to define another closed sectional shape similar to the above-mentioned second closed sectional shape by additionally providing a reinforcing member, such as for the damper stiffener, between the rear wheel arch and the rear pillar. However, such an approach would lead to an increased weight of the vehicle. Particularly, if the thickness of the vehicle body is increased to increase the mechanical strength of the vehicle body during travel of the vehicle, the vehicle would significantly increase in weight. Further, depending on the design of the vehicle, the increased thickness of the vehicle body would lower a degree of freedom of the reinforcing member but also reduce the capacity of a baggage chamber of the vehicle.    Prior Art Literature: Japanese Utility Model Application Laid-Open Publication No. HEI-3-44079.